[#204 state:fixed] Added a message after re-prioritization telling how many dupe groups were changed by it.

core/app.py

@@ -502,9 +502,13 @@ class DupeGuru(RegistrableApplication, Broadcaster):
         return False
     
     def reprioritize_groups(self, sort_key):
+        count = 0
         for group in self.results.groups:
-            group.prioritize(key_func=sort_key)
+            if group.prioritize(key_func=sort_key):
+                count += 1
         self._results_changed()
+        msg = tr("{} duplicate groups were changed by the re-prioritization.").format(count)
+        self.view.show_message(msg)
     
     def reveal_selected(self):
         if self.selected_dupes:

core/engine.py

@@ -290,10 +290,13 @@ class Group:
     
     def prioritize(self, key_func, tie_breaker=None):
         # tie_breaker(ref, dupe) --> True if dupe should be ref
+        # Returns True if anything changed during prioritization.
         master_key_func = lambda x: (-x.is_ref, key_func(x))
-        self.ordered.sort(key=master_key_func)
+        new_order = sorted(self.ordered, key=master_key_func)
+        changed = new_order != self.ordered
+        self.ordered = new_order
         if tie_breaker is None:
-            return
+            return changed
         ref = self.ref
         key_value = key_func(ref)
         for dupe in self.dupes:
@@ -303,6 +306,8 @@ class Group:
                 ref = dupe
         if ref is not self.ref:
             self.switch_ref(ref)
+            return True
+        return changed
     
     def remove_dupe(self, item, discard_matches=True):
         try:

core/tests/engine_test.py

@@ -656,7 +656,7 @@ class TestCaseGroup:
         g.add_match(m2)
         g.add_match(m3)
         assert o1 is g.ref
-        g.prioritize(lambda x:x.name)
+        assert g.prioritize(lambda x:x.name)
         assert o3 is g.ref
     
     def test_prioritize_with_tie_breaker(self):
@@ -703,6 +703,14 @@ class TestCaseGroup:
         g.prioritize(lambda x: -x.size)
         assert g.ref is o1
     
+    def test_prioritize_nothing_changes(self):
+        # prioritize() returns False when nothing changes in the group.
+        g = get_test_group()
+        g[0].name = 'a'
+        g[1].name = 'b'
+        g[2].name = 'c'
+        assert not g.prioritize(lambda x:x.name)
+        
     def test_list_like(self):
         g = Group()
         o1,o2 = (NamedObject("foo",True),NamedObject("bar",True))